Valve-dressing tool.



No. 722,222. PATENTED MAR. 10; 1903,

J. I. FUHRMANN.

VALVE DRESSING TOOL.

APPLICATION FILED NOV. 7, 1901.

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JOHN T. FUHRMANN, OF ST. PAUL, MINNESOTA.

VALVE-DRESSING TOOL.

SPECIFICATION forming part of Letters Patent No. 722,222, dated March 10, 1903.

Application filed November '7, 1901. Serial No. 81,383. (No model.)

To all whom it may concern.-

Be it known that 1, JOHN T. FUHRMANN, a citizen of the United States, residing at St. Paul, in the county of Ramsey and State of Minnesta,have invented certain new and useful Improvements in Valve-Dressing Tools; andI do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My present invention has for its object to provide an improved device fordressing valveseats; and to this end it consists of the novel devices and combinations of devices hereinafter described, and defined in the claims.

My improved valve-dressing tool was especially designed and is especially adapted for dressing valve-seats of the well-known lVestinghouse and New York types of triple valves. The valve-seats in question are usually formed in bushings or sleeves and have usually been dressed by hand by the use of a file or scraping-tool. This mode of dressing valves is slow, and hence costly.

By my invention I provide a device by means of which and without removing the bushing containing the valve-seat the valveseat may be dressed quickly and accurately.

My invention is illustrated in the accompanying drawings, wherein like characters indicate like parts throughout the several views.

Figure 1 is a View, partly in section, but with some parts shown in full, illustrating my improved valve-dressing device in working position on a valve-seat of a valve-bush? ing such as employed in the well-known New York triple valve. Fig.2 is a longitudinal section taken centrally through my improved valve-dressing tool, some parts being shown in full. Fig. 3 is a detail view, partly in side elevation and partly in section, showing the tool or cutter-block and its actuating-wedge or cam-plunger, said parts being separated. Fig. l is a plan view ofa cam-plunger. Fig. 5 is a transverse section on the line 00 00 of Fig. 2. Fig. 6 shows a portion of the tool looking at the face of the cut, and Fig. 7 is a face view of some of the mandrel-guide plates.

The numeral 1 indicates a section of the triple valve, the same containing the valveseat bushing or sleeve 2, having the valveseat 3. The section or casting l is provided with end flanges aand 5 and screw-threaded hub 6.

The numeral 7 indicates amandrel-guiding plate which is detachably securable to the flange 4 by nutted bolts 8 or otherwise and is provided with an offset portion 9, which telescopes into the cavity surrounded by the flange 4aud serves to properly center the said plate. In axial line with the passage through the sleeve or bushing 2 said plate 7 is provided with a seat or perforation 10, having an offset portion 11, which alines or registers with the valve-seat 3, but is somewhat deeper. Another guide-plate 12 is securable to the flange 5, as shown, by means of machinescrews 13. This plate 12 is countersunk at 14, so thatit fits closely over the screw-threaded hub 6 and is accurately centered thereby. At its center this guide-plate 12 is provided with a mandrel-seat 15 with offset portion 16, which parts aline, respectively, with the passage through the bushing 2 and with the valveseat 3. The guide-plates 7 and 12 constitute a jig, and hence may be very properly termed jig-plates.

The numeral 17 indicates a heavy mandrel or cylindrical stem which is adapted to be passed through the sleeve 2 and to be accurately guided by the seats and in the guide-plates 7 and 12, respectively. Extending from one end more than half-way through the same the mandrel 17 isprovided with a cylindrical plunger-seat 18 and at its intermediate portion it is provided with a diametrically-extended seat 19, which intersects the said seat 18. A cutter-block 2O fits snugly within the seat 19 and works transversely thereof. On one face this block 20 is provided with a hardened cutting-plate 21, having teeth 22, which for an important purpose are variably spaced. Preferably beginning from left toward the right with respect to Figs. 1, 2, 3, and 6 the length or spacing of the teeth increases successively. The cutting-plate 21 is detachably secured to'the block 20 by screws 23, and to securely hold the same against slipping it is provided with lug 24, which is countersunk into the face of said block 20.

At its back the block 20 is formed with a slot 25 and with cam-grooves 26, which cam grooves extend at an oblique angle to the axis of the mandrel 17. The block 20 is adjusted transversely of the mandrel 17 by means of the cam-plunger 27, which works axially in the seat 18 and is provided with cam-flanges 28. The cam-flanges 28 work in the cam-grooves 26 and extend at the same angle with respect to the axis of the mandrel.

29 is a thrust nut which, as shown, is screwed into the open end of the seat 18.

30 indicates a thrust-screw which is swiveled in the thrust-nut 29, being held against endwise movements by an outer head 31 and inner collar 32. The inner end of this thrustscrew Works with screw-threaded engagement in a screw-threaded seat 33, formed in the adjacent end of the cam-plunger 27. The head 31 is formed angular to permit the application of awrench thereto, and preferably this head as well as the hub of the nut 29 are provided with cooperating graduations or marks, (best shown in Fig. 1,) which serve to indicate the amount of adjustment given to the cutter 21. i

As is evident, the desired adjustment may be given to the block 20 and its cutter-plate 21 by adjusting the cam-plunger 27 in the one direction or the other. When the said plunger is moved inward, the said block and cutter-plate will of course be moved outward. It will also be noted that by the cooperating cam-grooves 26 and cam-flanges 28 the said block 20 is positively locked against vibration or movement in either direction. It will also be noted that the cutterplate 21 is slightly wider than the block 20, and hence serves as a stop to prevent the said block and cutter-plate 21 from being moved inward far enough to permit the cam-plunger or wedge 27 being withdrawn from the seat 18 without having first removed the said cutter-plate.

. The toolis intended to be operated by hand; but it is of course evident that it may beotherwise operated.

. The operation of the tool is probably evident from the illustration given in Fig. 1. The offset portions 11 and 16 of the seats 7 and 15, respectively, permitthe cutting-plate 21 to be moved freely to and from its work and also serve to hold the said cutting-plate in proper alinement with the valve-seat 3 when removed therefrom. Since the mandrel 17 is guided entirely by the seats in the guideplates 7 and 12, the valve-seat will be accurately dressed, even when the said mandrel does not closely fit the bushing 2.

The variable spacing of the teeth of the cutter-plate prevents chattering of the tool.

The tool above described is of course capable of considerable modification within the scope of my invention. Where the valveseat to be dressed is concave or cylindrical, the cutting-teeth mayof course be formed on the properly-curved lines.

WVhat I claim, and desire to secure by Letters Patent of the United States, is as follows:

1. A tool for dressing valve-seats in the bushings of air-brake valves or the like, consisting of a cylindrical mandrel of approximately uniform diameter from end to end so that it may be passed entirely through the valve-bushing, a transverse slot in said mandrel, the sides and ends of which form guide- Ways, a cutting-tool guided in said slot and having a plurality of transversely-arranged teeth, an adjusting-wedge slidably mounted in a bore of the mandrel and arranged to act on the cutter to adjust it in said slot radially of the mandrel, and means reacting against the mandrel for moving the wedge.

2. A tool for dressing valve-seats in the bushings of air-brake valves, or the like, consisting of a cylindrical mandrel of approximately uniform diameter from end to end, so that it may be passed entirely through the valve-bushing, a transverse slot in said mandrel, the sides and ends of which form guideways, a cutting-tool guided in said slot and having a plurality of transversely-arranged teeth, an adjusting-wedge slidably mounted in a bore of the mandrel and arranged to act on the cutter to adjust it in said slot radially of the mandrel, and means reacting against the mandrel for moving the wedge, in combination with guiding jig-plates scour-able to the valve, for guiding said mandrel.

In testimony whereof I affix my signature in presence of two witnesses.

JOHN T. FUHRMANN. 

